the EDITOR'S column L.T. H a l l e t t , E d i t o r
\
NEW, consistent set of values for the physical constants has been recommended by the Committee on F u n d a m e n t a l Constants of the N a tional Academy of Sciences—Na tional Research Council (NAS— NRC). T h e N a t i o n a l B u r e a u of S t a n d a r d s has adopted these values for use in all N B S publications, ex cept where for some special reason the author is required to use others [Nat. Bur. Std. {U.S.), Tech. News Bui., 47, 175 (1963)]. Previously, several lists of "best v a l u e s " for the physical constants were available. T h e worker then had to m a k e a choice as to which list he was going to follow. T h e N A S - N R C Committee re ports: " I n arriving a t these values the Committee h a d available a large amount of experimental information not all of which appeared to be of consistent reliability and accuracy. I n some cases where experiments were suspected of having significant errors and the results were discrep ant with other experimental results believed to be of greater reliability, the d a t a were rejected. Inclusion of these rejected d a t a would have altered the values in the table some w h a t but not greatly." T h e new values of the constants are given in Table I. The uncer tainties assigned represent estab lished limits of error; namely, three s t a n d a r d errors based on s t a n d a r d deviations assigned to the d a t a re tained for input to the least-squares adjustment. Those calculated from the residuals of the final leastsquare adjustment are even smaller. I t is therefore unlikely t h a t the t r u e value of a n y of the constants differs from the value given in the table by as much as the stated uncertainty. The uncertainties in constants com puted from elemental ones m a y be either greater or less t h a n is o b tained by simple combination of the
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VOL.
36, NO. 1, JANUARY 1964
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63
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